This invention is directed to the providing of a suitable plastic sheet support clip structure which is designed to be utilized in combination with a plastic sheet in effectuating a water impervious seal at the rearward end of a truck having a closable door assembly. This plastic sheet and support clip structure does not form the basic protective shielding as to a door opening but is only intended as a supplementary structure for increasing the ease with which the seal can be effectuated and decreasing the time, cost and wasted materials associated with the current methods of coping with this situation. The invention allows an effective seal to be formed and thus aids in preventing the entry of water into the cargo compartment of the truck.
Cargo trucks having a rear door assembly must guard against the seepage of water into the cargo area. Although trucks with dual hinged door assemblies are better able to seal tightly because of overlap around their edges, such as many refrigeration trucks and tractor-trailer trucks also provide with sealing gaskets, those trucks provided with such door assemblies as well as those with roll-down doors permit water to seep in from the sides and bottom of the door. The custom is for truckers to attach an inexpensive sheet of plastics, whose width extends across the width of the cargo area, to the top of the sides of the truck body adjacent to the rear door. The plastic sheet extends from the top of the truck to just beyond the point that the rear door latches. After the sheet is fastened to the side walls of the cargo compartment the rear door is closed and the lower edge of the plastic sheet is pulled between the bottom of the door and the floor of the truck itself. The door is then closed and the latch is fastened. The plastic sheet then effectively prevents the entrance of water and consequent damage to the cargo.
The attachment of the sheet to the upper side walls has been accomplished by a variety of means, all of which possess limitations. One often used method relies on stapling of the sheet to a wooden inner frame structure of the truck or van body. If the particular truck does not have the wood frame or wall into which the staples may be driven, any attempt to make the staple fasten to metal is an exercise in futility. If the truck does have a wood frame then several staples must be used to securely support the weight of the sheet. Over a period of time literally thousands of staples must be used. Additionally there is the cost of staplers or stapling guns which can be lost or stolen.
Another method of attachment relies on the use of adhesive tapes, such as masking tape. When the side walls of the truck are made of metal, tape has been the only method that was practical. Copious strips of tape are applied to the upper corners of the sheet in an attempt to enable the tape to support the sheet. The amount of tape necessary for the proper degree of adhesion varies with the type and brand of tape used, and also with the weather conditions. Low temperature decreases the ability of the tape to stick effectively. Also, dampness and moisture adversely affects the adhesion of the tape. Therefore, in addition to being costly, the general effectivity and dependability of tape is not very good.
In addition to the two above methods there is one method relied upon by truckers when all else has seemingly failed. Sometimes truckers puncture holes in the wood side walls and attempt to secure the corners of the plastic sheet in these holes and support the sheet in this fashion. Needless to say, this method exposes the trucker to the potential of physical harm because of the wood splinters or slivers through which he must continue to fasten subsequent plastic sheets. Also, this adversely affects the value of the trailer or truck.
Therefore the above methods for attaching the plastic sheet result in excess cost, possible health dangers, frequently ineffective seals and consequently damage to cargo, and considerable labor, and time in first locating the fastening materials and then in securely fastening the sheet to the van body.